25.sort_hashmap.java

//Sort Hashmap based on key values using Treemap
import java.util.*;
public class sort_hashmap {
 public static void main(String[] args) {
 HashMap<Integer,String> hash_map = new HashMap<>();
 int n;
 String map_value;
 int map_key;
 Scanner sc = new Scanner(System.in);
 System.out.println("Enter size of Hash map: ");
 n = sc.nextInt();
 //User-input and put function to insert into hashmap
 for(int i=0;i<n;i++){
 System.out.println("Enter key in hash-map at "+(i+1));
 map_key = sc.nextInt();
 System.out.println("Enter value in hash-map at "+(i+1));
 map_value = sc.next();
 hash_map.put(map_key,map_value);
 }
 System.out.println("Sorting Hash map based on key ");
 TreeMap<Integer, String> tree_map = new TreeMap<>(hash_map);
 for (Integer integer : tree_map.keySet()) {
 int key = integer;
 System.out.println(key + ": " + hash_map.get(key));
 }
 }
}